A bogie frame for railroad vehicle includes two, right and left, side beams arranged to extend in a rail direction (a front-rear direction of the bogie frame) and two, front and rear, lateral beams arranged to extend in a rail-tie or sleeper direction (a right-left direction of the bogie frame), the side beams and the lateral beams being joined to each other. Conventionally, various configurations are proposed for the bogie frame for railroad vehicle having such a shape. For example, FIG. 15 shows a bogie frame for railroad vehicle disclosed in Patent Document 1 listed below. A bogie frame 100 for railroad vehicle includes side beams 101 each having spring caps 111 at both ends in a front-rear direction and two lateral beams 102 extending through the side beams 101 and being welded thereto in respective penetrating portions. The lateral beams 102 are made of round steel pipes. Two lateral beams 102 are integrally configured with top plates 112 and bottom plates 113.
Furthermore, Patent Document 2 listed below discloses a bogie frame including lateral beams and side beams configured as a vertically two-divided structure. This bogie frame for railroad vehicle consists of an upper frame and a lower frame, each having a recessed cross-section formed by press molding, the upper and lower frames being made integral by welding. Furthermore, Patent Document 3 listed below also discloses a side beam for use in a bogie frame for railroad vehicle. The side beam is made of a long flat plate by press work.